Transom question - Grumman 16ft Aluminum Boat

[drwalleye]

I've recently purchased a 1993 Grumman fishing boat that has been very abused in the past. It's been left to sit in the rain for quite a few years and has had multiple owners it appears...

Going into it, I knew the deck was going to have to be replaced, and as I started the process of re-doing the floors, I was referred to these forums by a friend to help answer some questions.

After removing the first layer of rotten wood, I noticed that they had just put a second floor on top of the original. What a mess... Anyway, now that I've figured out how much work the floors are going to take and now how nice the boat is going to be when it's done, I've started to wonder about the transom.

The transom cap has been replaced in the past (not sure when), and they did a terrible job using very thin tin and then just sealed the heck out of it.

It seems that there is a lot of info on replacing the transom in these forums, but I couldn't find anything about if you can just buy replacement caps or if they need to be custom made? I also would like to get matching corners for the transom, any idea where to go about getting/ordering them?

Thanks for any info you can provide!

 

[danond]

Re: Transom question - Grumman 16ft Aluminum Boat

Caps and corners are tough. Some people have had them made (created custom molds). Caps aren't as hard - it's just bent stainless. You can do that yourself, or take it to someone and have one bent for you.

Trying to find replacements will be a waste of time. Easier to have them made!

 

[Bob_VT]

Re: Transom question - Grumman 16ft Aluminum Boat

I've recently purchased a 1993 Grumman fishing boat that has been very abused in the past. It's been left to sit in the rain for quite a few years and has had multiple owners it appears...

Going into it, I knew the deck was going to have to be replaced, and as I started the process of re-doing the floors, I was referred to these forums by a friend to help answer some questions.

After removing the first layer of rotten wood, I noticed that they had just put a second floor on top of the original. What a mess... Anyway, now that I've figured out how much work the floors are going to take and now how nice the boat is going to be when it's done, I've started to wonder about the transom.

The transom cap has been replaced in the past (not sure when), and they did a terrible job using very thin tin and then just sealed the heck out of it.

It seems that there is a lot of info on replacing the transom in these forums, but I couldn't find anything about if you can just buy replacement caps or if they need to be custom made? I also would like to get matching corners for the transom, any idea where to go about getting/ordering them?

Thanks for any info you can provide!

[/IMG]

Welcome to iboats.

Abuse and aluminum boats goes hand in hand. That is a good point...... the aluminum boat will normally recover nicely.

There are some really nice aluminum boat conversions in out completed project section that you should look at. http://forums.iboats.com/forumdisplay.php?f=407

The transom cap is normally made of very thin aluminum and if your cap is tin .... I would replace it asap. Aluminum is very prone to galvanic corrosion and tin can set that reaction off which causes cancer in the aluminum. I have never seen caps made from stainless steel but I guess if you wanted to make one it might be extra work.

New wood over old wood usually works for a season and it is a band aid repair. It is time to rip out the old and install the new. You will need to see what is under the wood and decide your future from there. Regardless of what you use ....... it will have to be sealed up tightly from the water.

Keep in mind the new pressure treated plywoods will react with the aluminum in the hull so ask prior to purchase.

Look at the hull when it is stripped...... rivets should be re-bucked (tightened up) and sealer (gluvit) applied if needed.

We have more aluminum boat restoration expertise here than can be found anyplace else.

 

[5150abf]

Re: Transom question - Grumman 16ft Aluminum Boat

Ya, people do some funny things to boats.

Recovering a floor is almost inexcusable, it was cheap and easy and made the problem go away, for a while.

Decks on aluminum boats are pretty easy although I am pretty sure you will find waterlogged foam when you pull the deck off but even that isn't to hard to fix.

Maybe try a boat salvage yard for corner caps, you should be able to find some proper cast ones and those are pretty interchangable, the ones that are on it are next to worthless, they didn't do too bad of a job on the cap though, it pretty tough to bend channel like that, is it galvanized sheet?

See if you can find some thin aluminum sheet to make some new caps out of, I think you are on your own with that though, proabably cna't be had at a salvage.

Looks like a pretty recent job on the transom so I would see if it is okay before replacing it. maybe pull the cap and see what is under it.

Should be a really nice boat when you are done.

 

[tmcalavy]

Re: Transom question - Grumman 16ft Aluminum Boat

Crawl in there and poke at the transom with an awl...it should be solid, not mushy or soft. With the homemade tin cap/edge, it may have already been replaced...check it twice because you found a band-aid patch on the floor. Transoms in that kind of boat aren't hard to do...hardest part is getting the old one out and that's not too bad if its rotted and soft.

 

[drwalleye]

Re: Transom question - Grumman 16ft Aluminum Boat

Thank you guys for the quick responses! I removed one of the corners and was able to get a quick feel of the shape that the transom wood is in. It doesn't appear to be rotten as far as I can tell. I do happen to know a guy who runs a machine shop, I'll have to see if he can fashion me a new cap and some corners.

As mentioned above, there was some water-logged foam underneath the old floor. But to my surprise, it was only the back 2-3 feet or so that appeared to be soaked or saturated. I imagine the angle the boat was stored in when it was left to sit with water in it played a role.

From what I read in here, it makes the most sense to re-do all of the foam if it's water-logged. After the purchase of all my materials, I hate to add more work and money to the project. But I also hate to do things halfway and cut corners. I plugged a few holes in the back of the boat this weekend that I knew were causing leaks. I'm going to get it into the water sometime later this week to check for additional leaks. If it stays dry, I'll leave the old foam in. (which has dried out considerably in the past week or so that the floor has been off of it) If water seeps in, I'll be tearing the foam out to find the leaky rivets/seams and seal them before I put the new floor and carpet in.

I didn't take too many pics to begin with when I started, but I'll have to start a thread and post the progress I continue on. Thanks again for your help!

 

[gunner1]

Re: Transom question - Grumman 16ft Aluminum Boat

Instead of taking the boat out on the water to check for leaks you could do what I did and simply take a hose and fill the boat to the water line. That way, you can get under the boat to visually check for leaks and mark them with a Sharpie for later repair. If you do do this, just make sure yo don't put in too much water.

 

[drwalleye]

Re: Transom question - Grumman 16ft Aluminum Boat

I did try this to begin with. I knew the boat had a few leaks somewhere, because it was taking on water last fall when I first got the boat and just wanted to launch it to try it out.

I used a hose and ran water into the bottom of the boat (I didn't fill it all the way to the waterline though because water came streaming out of 2 rivet holes). The only leaks I could find were 2 holes that were drilled through the transom to mount a depth finder or some other piece of equipment that were not sealed or the material used to seal them didn't hold. If you strain your eyes at the first picture I posted, you'll see that there is a number of rivets (~20) that someone had put into the bottom of the transom and sealed. So I removed them and sealed it all with good old JB Weld.

I have at least 4 small lakes within 10min of my house, so it wouldn't be too tough for me to just run to the lake for a few minutes to test it out.

 

[Silver Heels]

Re: Transom question - Grumman 16ft Aluminum Boat

For the cap over the transom on my 14' lund, I went to a place nearby which handles steel, aluminum, and stainless tubing, channel, and pipe. I told them I needed a 4' hunk of 3 sided aluminum channel and they cut me a piece that was just the width and thickness I was looking for. My transom was straight across though. It looks like yours wouldn't be very easy with the curves and angles.

 

[shawnc]

Re: Transom question - Grumman 16ft Aluminum Boat

I will be curious to follow your progress. My dad and I are getting an identical boat in vermont to leave at a fishing camp and we know the floor is soft and were also told the transon could be soft, but not sure at this time. On the one we are looking at, it looks like the fuel tank slid forward 1-2" under the floor. The sending unit and vent tube are not directly over the access holes. Did you happen to notice how the tank is secured under the floor? As in straps or plastic tabs on the tank?

If you could, please take some pictures of your transom disassembly. They would be extremely helpful.

Thanks and good luck with the restore. I had fun when I restored a 15 ft Haulin Bass fiberglass boat 2 winters ago. Luckily the transon was fine, but the foam was shot. I used the green stuff from Lowe's and cut strips to put under the floor. That boat was small enough to not need stringers.

Shawn

 

[jasoutside]

Re: Transom question - Grumman 16ft Aluminum Boat

Old thread fellas.